TY - JOUR
T1 - The addition of small molecules to (η-C5H5)2Rh2(CO)(CF 3C2CF3). X. Addition of terminal alkynes; the formation of bridging carbonyl cyclobutenyl intermediates (η-C5H5)2Rh2(μ-CO)-[ η1,η3-C4(CF3)2 HR] and their facile conversion to binuclear metalladine complexes (η-C5H5)2Rh2[η2 ,η4-C4(CF3)2HR].
AU - Dickson, Ron S.
AU - McLure, Felicity I.
AU - Nesbit, Rhonda J.
N1 - Funding Information:
This work was supported by grants from the Australian Research Grants Scheme and the Monash University Special Research Fund.
PY - 1988/7/26
Y1 - 1988/7/26
N2 - Reaction occurs immediately when solutions of (η-C5H5)2Rh2(μ-CO)( μ-η2-CF3C2CF3) (1) in hexane are treated with HCCR (R = H, CF3 or Ph), and the cyclobutenyl complexes (η-C5H5)2Rh2(μ-CO) [μ-η1,η3-C4(CF3) 2HR] (2) separate in near quantitative yield. CO is lost fairly rapidly from solutions of 2 in polar organic solvents, and the metallacyclopentadiene complexes (η-C5H5)2Rh2[μ-η 2,η4-C4(CF3)2 H R] (3) are formed. The reactions between HCCR (R = Pr or CH2CO2Me) and 1 in hexane are also fast, but no precipitate is formed; infrared spectroscopy indicates that 2 (R = Pr or CH2CO2Me) is present in the reaction solution, but there is rapid conversion into 3 (ca. 80% yield after TLC work up). Slower reactions (2-5 min) occur between 1 and HCCR (R = CH2CH2CH2CCH or CMe=CH2) in hexane, and again all the products remain in solution. It is possible to separate 2 (R = CH2CH2CH2CCH or CMeCH2) (up to 65% yield obtained) from the corresponding 3 by immediate TLC, but 2 is converted fairly rapidly into 3 when left in solution. The reaction between 1 and HCCSiMe3 is significantly slower (ca. 15 min), and gives 3 (R = SiMe3) (64% yield) and (η-C5H5)2Rh2(CO)2 CF3C2CF3 (21%) as major products. Another product, spectroscopically identified as (η-C5H5)2Rh2(μ-CO) [μ-C(O)C(CF3)C(CF3)](μ-HC2SiMe 3 ) (7) can be isolated in significant amount only when TLC of the reaction solution is performed within 10 min of mixing the reactants. Spectroscopic analysis indicates complete regioselectivity in the formation of all metallacyclopentadiene complexes 3, with the H and R groups (from HCCR) located in the 3- and 2-positions respectively of the 1-metallacyclopentadiene ring.
AB - Reaction occurs immediately when solutions of (η-C5H5)2Rh2(μ-CO)( μ-η2-CF3C2CF3) (1) in hexane are treated with HCCR (R = H, CF3 or Ph), and the cyclobutenyl complexes (η-C5H5)2Rh2(μ-CO) [μ-η1,η3-C4(CF3) 2HR] (2) separate in near quantitative yield. CO is lost fairly rapidly from solutions of 2 in polar organic solvents, and the metallacyclopentadiene complexes (η-C5H5)2Rh2[μ-η 2,η4-C4(CF3)2 H R] (3) are formed. The reactions between HCCR (R = Pr or CH2CO2Me) and 1 in hexane are also fast, but no precipitate is formed; infrared spectroscopy indicates that 2 (R = Pr or CH2CO2Me) is present in the reaction solution, but there is rapid conversion into 3 (ca. 80% yield after TLC work up). Slower reactions (2-5 min) occur between 1 and HCCR (R = CH2CH2CH2CCH or CMe=CH2) in hexane, and again all the products remain in solution. It is possible to separate 2 (R = CH2CH2CH2CCH or CMeCH2) (up to 65% yield obtained) from the corresponding 3 by immediate TLC, but 2 is converted fairly rapidly into 3 when left in solution. The reaction between 1 and HCCSiMe3 is significantly slower (ca. 15 min), and gives 3 (R = SiMe3) (64% yield) and (η-C5H5)2Rh2(CO)2 CF3C2CF3 (21%) as major products. Another product, spectroscopically identified as (η-C5H5)2Rh2(μ-CO) [μ-C(O)C(CF3)C(CF3)](μ-HC2SiMe 3 ) (7) can be isolated in significant amount only when TLC of the reaction solution is performed within 10 min of mixing the reactants. Spectroscopic analysis indicates complete regioselectivity in the formation of all metallacyclopentadiene complexes 3, with the H and R groups (from HCCR) located in the 3- and 2-positions respectively of the 1-metallacyclopentadiene ring.
UR - http://www.scopus.com/inward/record.url?scp=0346904689&partnerID=8YFLogxK
U2 - 10.1016/0022-328X(88)87034-7
DO - 10.1016/0022-328X(88)87034-7
M3 - Article
AN - SCOPUS:0346904689
VL - 349
SP - 413
EP - 426
JO - Journal of Organometallic Chemistry
JF - Journal of Organometallic Chemistry
SN - 0022-328X
IS - 3
ER -